So when the problem is saying that 3 out of every 8 students prefer strawberry to vanilla, it means that 3/8 of all students like strawberry better. There are 160 students in total, so that means 3/8 * 160 or 60 students like strawberry.

You use the same principles as if there's only one inequality sign.
But if it makes it easier for you, divide the problem into two separate inequalities:
-1 < 3 - 5m < 3 is the same thing as saying that -1 < 3 - 5m and 3 - 5m < 3.
Now, normal inequality rules apply. First...

See how the two points have the same x-value (-3)? That means it's a vertical line and comes in the form of x = something. Here, that something is -3. It's not possible to write vertical lines in slope-intercept form, so x = -3 would be the answer to your question.

I found an alternative answer.
We can first factor (2s - 3)/(s2 - 4) into A/(s+2) + B(s - 2). By the solution methods in your book, you should get A = 7/4 and B = 1/4. We know that F(s) = A/(s - a) means that f(t) = e-at, so what you should get for the answer is f(t) = 7/4 * e-2t +...

From the question we can tell that Dan drove for 3 hours. Castel left the mall one hour before Dan, so she drove for 4 hours. For convenience's sake, we say that Castel drives with a speed of x; in this case, Dan's speed is x - 40 (he drives 40mph more slowly).
Now we can set up the equation:...